code: def closeEvent(self, event: QtGui.QCloseEvent) -> None:
      event.ignore()
      main: QtWidgets.QMainWindow = self.parent()
      dock_widgets = main.findChildren(QtWidgets.QDockWidget)
      dock_widgets = [w for w in dock_widgets if not w.isFloating()]
  
      self.setFloating(False)
      if len(dock_widgets) > 0:
          if self != dock_widgets[0]:
              main.tabifyDockWidget(dock_widgets[0], self)
          else:
              main.tabifyDockWidget(dock_widgets[1], self)
      else:
          main.addDockWidget(Qt.LeftDockWidgetArea, self)
  
file_path: PandasGUI/pandasgui/widgets/dock_widget.py
imports: from PyQt5 import QtCore, QtGui, QtWidgets
  from PyQt5.QtCore import Qt
label_desc: Use image node_id 6 for calling the DockWidget obj's underlying member method code with example usage: obj.closeEvent(event) without return types